[ Date Index ][
Thread Index ]
[ <= Previous by date / thread ] [ Next by date / thread => ]
Okay, This are a little hazy on what eirp is actually allowed these days. I've actaully spoke to one installation company that told me the limit is now 250mW in the UK - I always believed it was 100mW. I know in the US, that the rules change slightly when you're talking about a point ot point link. Once you add an Ae, you're supposed to lower the trasmitter power output by 1dB for each 2dB of Ae gain. I don't know if the UK also have that sort of ruling. Jon On Friday 25 Jul 2003 11:37 pm, Paul Weaver wrote: > On Saturday 26 July 2003 01:20, you wrote: > > So a directional aerial won't actually boost your transmit power, if you > > are to stay within the law, but will allow you a stronger receive signal, > > yeah? > > No. As wifi is a two-way signal, a decent antenna will boost your signal > 20+dB. Thats a 100-fold increase on the original signal. > > You transmit at 100mW, you lose some in the cable to the ariel, the air > between ariels, and the cable from the Rx ariel. You gain because of > ampliefiers and ariels. Typically you transmit at 10dB and receive at > -80dB. The total loss, of cable and air combined with the total gain of > amps and ariels, must be less then that 90dB difference. > > > I've seen some impressive statistics quoted using normal equipment > > strapped to an old satellite dish, I might try that some day... although > > I think it's still pretty much "line of sight". :-( > > 2.4GHz cant go through objects, so while LOS is possible, using multipath, > its not really probable. With full LOS you should push 10 miles by only > breaching the 100mw "by a little bit". > > -- > The Mailing List for the Devon & Cornwall LUG > Mail majordomo@xxxxxxxxxxxx with "unsubscribe list" in the > message body to unsubscribe. -- The Mailing List for the Devon & Cornwall LUG Mail majordomo@xxxxxxxxxxxx with "unsubscribe list" in the message body to unsubscribe.